【作者】 薛志孝；

【导师】 李迎新；

【作者基本信息】 天津医科大学 ， 生物医学工程， 2009， 博士

【摘要】 背景：青光眼是一种常见的眼科疾病,如果不对其进行正确的诊断和治疗,将会产生不可逆性失明。国际卫生组织在1996年提出,将21世纪的防盲治盲重点由白内障转向青光眼。激光青光眼手术为青光眼治疗提供了一个新的方法,但现有的激光手术方法对有些难治性青光眼仍不能有较好的疗效。因此,需要寻求更有效的、术中出血少或不出血的激光手术方法。目的：(1)开发一套具有自反馈功能的青光眼滤过手术系统,该系统具有自动判定手术进程、自动控制手术进程的功能,满足临床青光眼滤过术的手术要求,达到产品化的标准。(2)通过动物预实验和动物实验,验证该系统的有效性和安全性,提出规范的手术方式。材料和方法：(1)激光手术系统：应用射频CO2激光器、开关式激光电源、外科手术显微系统、光学接口等开发设计了射频CO2青光眼治疗系统。应用Visual C++6.0和Matalab编写了基于Windows XP和Win CE平台的系统程序。(2)动物实验：选用新西兰白兔40只,左眼行CO2激光巩膜切除联合虹膜切除术,右眼行传统小梁切除术。术后观察眼前房反应、滤过泡,测量并记录术前术后眼压,进行组织病理学检查。提出系统修改方案和手术方式修改方案。(3)高眼压模型实验：首次将高眼压模型应用于激光巩膜切除联合虹膜切除术的评价中。α—糜蛋白酶诱导产生兔高眼压模型24只48眼,左眼行改良后的CO2激光巩膜切除联合虹膜切除术,右眼行传统小粱切除术,术后观察前房反应、滤过泡、术前术后眼压和分期病理学检测。结果：(1)设计和完成一套射频CO2激光青光眼手术系统,并进行了调试和测试,该系统可有效地完成激光巩膜切除联合虹膜切除术。(2)动物实验结果：①前房反应：激光手术组术后前房反应轻微,传统手术组出现了前房出血或团块状渗出为主的前房反应,激光组出血少且吸快于传统手术组。②滤过泡：术后激光组功能性滤过泡明显多于传统手术组(P<0.05),且滤过泡持续时间长。③平均眼压：随观察时间的延长,实验组眼压升高速度快于对照组,术后14天和21天两组眼压出现统计学差异(P<0.05)。④组织病理学检查显示,与传统手术组相比,激光组术后无明显的出血和炎性增生,滤过道通畅时间长。(3)手术程序：巩膜瓣完成后,器械按压巩膜,使虹膜贴近巩膜,选用合适的激光参数照射,出现“红反射”后,当强度达到设定范围时,判定滤过道形成,选用低强度脉冲激光对巩膜瓣照射,预防粘连,缝合。结论：(1)采用射频CO2激光器实现了智能化的青光眼激光手术系统,用于巩膜切除联合虹膜切除术,在不同的工作模式下均可安全有效的实施手术；系统手术过程中的安全性能通过实验得到验证,达到了设计要求；系统操控简单,便于临床医生操作。(2)将基于HSI彩色空间的加权中值滤波算法和基于各项异性和平均值位移分割算法用于眼部图像预处理,提高了图像处理的效率。(3)首次将α—糜蛋白酶诱导产生的兔高眼压模型应用于激光巩膜切除联合虹膜切除术的评价,实验结果更符合实际情况。(4)术后眼压观察及病理学检测证明,应用本系统进行改良后的巩膜切除联合虹膜切除术,可以有效控制眼压,术后并发症少。(5)通过本次研究,提出了规范的激光巩膜切除联合虹膜切除的手术方式,对光照射剂量和手术进程评判标准均有明确说明,为后期临床实验和推广提供了支持。更多还原

【Abstract】 Background:Glaucoma is a common eye disease that can lead to irreversible blindness if left undiagnosed and untreated. In1996, World health organization advanced that The key point of Prevention and treatment of blindness shifted cataract to glaucoma. Laser surgery is a new therapeutic modality. However, the refractory glaucoma can not been effectively treated by current laser surgery. Therefore,a new laser surgical way that is more effective,less or no hemorrhage is needed.Purpose:(1) To develop a self-feedback glaucoma filtering surgery system, which can automatically judge and control the surgery process and meet the needs of clinic glaucoma surgery and product standard. (2)Animal trials were used to prove the safety and efficiency of this system. And a standard of surgery process is established.Materials and method:(1) A CO2 laser glaucoma surgery system was developed, which is consisted of radio frequency CO2 laser device, switching mode power supply (SMPS), surgical microscope system, optical interface and so on. The software system is explored based on Visual C++6.0 and Matlab, working under windows XP and Win CE.(2) Animal trials.40 New Zealand white rabbits were selected. CO2 laser sclerectomy with iridectomy (CLSI) surgery was performed in the left eyes of all rabbits. The traditional trabeculectomy surgery was performed in the right eyes. Anterior chamber inflammatory response, filter bleb and IOP were observed. And all the eyes were then enucleated and subjected to histopathological examination.(3)Intraocular hypertension rabbit model trials. To evaluate the efficacy and safety of the surgery system, intraocular hypertension rabbit models were established. Alpha-Chymotrypsin was used to induce intraocular hypertension rabbit models. CLSI was performed on the left eyes and traditional trabeculectomy was performed on the right eyes. Postoperative anterior chamber inflammatory reactions, filtering bleb, IOP and pathological presentations were observed. Results:(1) The design and debugging of RF CO2 laser glaucoma surgery system was finished and the surgery system could perform the LSI effectively.(2)①Anterior chamber inflammatory reactions. The incidence of anterior chamber inflammatory reactions in the laser group was lower than that in the control group. Hemorrhage was the primary presentation and disappeared faster in the laser group.②Filtering blebs. There were fewer functional filtering blebs with shorter duaration in the traditional surgery group (P<0.05).③Mean IOP. As time went by, mean IOP of control group was raised faster than experimental guoup. At 14 and 21 days, there was a significant difference in mean IOP between the two groups(P<0.05).④Pathological examination. Pathological examination showed that compared with the laser surgery group, the traditional surgery group had more serious hemorrhage and fiber proliferation, leading to shorter duration of filtering channel.(3) Surgical procedures. After sclera flaps were finished, the sclera was pressed in order to be close to the iris. We adjusted appropriate laser parameter, judge red reflex intensity and after the irradiation, the sclera flaps were irradiated in low-power pulse mode laser to prevent conglutination. After the above procedures, the wound was sewed up.Conclusions:(1) RF CO2 laser glaucoma surgery system is an intelligent system which can safely and effectively finish the surgery in different modes. The system can meet the needs of the Surgical safety and expectant aim. (2) Weighted algorithms of median filtering based on the HSI color Space and image segmentation based on anisotropic algorithms and Mean Value displacement enhance the robustness of the system.(3) In order to approach the real condition, intraocular hypertension rabbit models induced by Alpha-Chymotrypsin was used to evaluate the laser glaucoma surgery. (4) The CLSI can effectively Control the mean IOP with fewer complications. (5) In this study, the standards of CLSI progress were established. The exposure dose and surgery degree were definitely illuminated, laying a foundation for clinical trials and popularization.更多还原